1. Field
One or more embodiments relate to an image processing apparatus and method, and more particularly, to an apparatus and method that may perform modeling of lighting environments and render an image.
2. Description of the Related Art
Currently, research about realistically rendering an object of a three-dimensional (3D) model has been actively conducted. To render the 3D model, modeling of lighting environments in addition to object information may need to be appropriately performed.
Among researches of modeling lighting environments, Peter-Pike Sloan, Jan Kautz, and John Snyder' paper titled “Precomputed Radiance Transfer for Real-Time Rendering in Dynamic, Low-Frequency Lighting Environments” (ACM Transactions on Graphics, Proceedings of the 29th Annual Conference on Computer Graphics and Interactive Techniques (SIGGRAPH), pp. 527-536. New York, N.Y.: ACM Press, 2002) discloses a method of obtaining spherical harmonics (SH) coefficients by projecting low frequency lights to basis functions for SH.
However, the above method may have some constraints in specular or glossy expression in an environment where small light sources are arranged in a complex form.
Modeling of lighting environments using virtual point lights (VPL) may be useful for the specular or glossy expression. However, it may be inefficient in that a relatively large number of VPLs may be used to express a large area light.